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How to measure distances and objects with the mobile camera

23 mayo, 2021

Our mobile is used for a huge number of functions but sometimes the simplest ones are overlooked. One of its most useful and simple uses is that of measure distances with the camera or mobile screen. Simply take your mobile, point the camera at the object you want to measure and the application will tell you the centimeters or meters it occupies or is tall.

Equivalently, we can also install ruler apps for android which allow us to use the device as a small rule. Very useful for measuring small objects, since in this case the size of the mobile will be a limiting factor. Here we leave you various methods to measure objects with your mobile, from the most modern that use ARCore augmented reality to the most basic that work on any type of mobile.

ARuler: measure objects with augmented reality


We started this little tutorial to measure objects with one of the most powerful applications. This is ARuler, an application that, through augmented reality, allows us measure distances, angles, areas and volumes of any object that we are focusing with the camera.

The only requirement is leave the object still on the table or a surface and by means of the mobile we will mark the points. The result is quite accurate, what happens is that it is not so easy to handle.

Ikea Place, its augmented reality application to decorate your home comes to Android phones with ARCore

In order to use it, you will need a mobile compatible with augmented reality. At the moment it is limited to the Google Pixel, Galaxy S9, S8, S7, OnePlus 5 or Huawei P20, but over the next few months it will reach more models. ARruler is completely free and represents the future of mobile measurement tools.

ARuler - (AR) for measurements

ARuler – (AR) for measurements

Smart Measure

The next application to measure is Smart Measure, a tool that allows know the distance an object is and its height, making use of basic trigonometry.

Smart Measure is not easy to calibrate, please be patient

We must place the camera at a certain height, press to mark a reference and then move the mobile so that the distance traveled is determined from the angle. The result is usually correct although it is difficult to calibrate, since a small movement can result in a quite large variation of the distance.

We recommend Smart Measure for outdoors and long distances. It is a free application although it contains quite a few ads. The full version that includes all the tools is priced at 2.99 euros.

Rangefinder: Smart Measure

Rangefinder: Smart Measure

Measure and align

Measure With Mobile

Two other tools that use the mobile camera to measure distances are ‘Measurement Tools’ and ‘3D Plummet’. The second of them is more complete although they have a similar operation based on choosing a point and depending on the angle determines the distance.

In 3D Plummet we can check if an object is fully vertical or horizontal. It also allows us to know the length and width of an object and in general have a frame of reference on the size of that point that we are focusing with the camera.

Measurement tools

Measurement tools

Measure and Align - 3D Plummet

Measure and Align – 3D Plummet

Rules for Android: how to measure with the screen

Ruler For Android

If what you want to measure are small objects, nothing is easier and simpler than the ruler applications for Android. The screen of our mobile will be divided into multiple lines representing a ruler and we can by tapping mark a specific position.

Three useful apps to measure small objects with the mobile screen

They are lightweight and well-designed applications. Some are very simple, others, for example, have two axes, ideal for measuring a coin, for example, and others are a toolbox where the ruler is simply one of its multiple functions.

The mobile can be a toolbox with a lot of potential. Sometimes you just need to know how to use what at all times. We hope these applications are useful to you and you can have a ruler handy in case you need it.

Measure (Material Ruler)

Measure (Material Ruler)

Physics Toolbox Sensor Suite

Physics Toolbox Sensor Suite